DNA code of rice mapped

Greater global food yield seen in breakthrough

NEW YORK -- A team of scientists from 10 countries has deciphered the genetic code of rice, an advancement that should speed improvements in a crop that feeds more than half the world's population.

It's the first crop plant to have its genome sequenced, which means scientists identified virtually all the 389 million chemical building blocks of its DNA. Certain sequences of these building blocks form genes, like letters spelling words.

The advance will help breeders produce new rice varieties with traits such as higher yield, improved nutritional content, and better resistance to disease and pests, said one of the leaders of the project, W. Richard McCombie of Cold Spring Harbor Laboratory in New York.

''I would think this is going to help people find genes and probably enhance the crop in well under 10 years," McCombie said.

The work is reported in today's issue of the journal Nature by the International Rice Genome Sequencing Project, which was established in 1998.

The effort was led by Japanese researchers.

In the Nature report, scientists estimated rice contains 37,544 genes but said that figure will be revised with further research. Humans have 20,000 to 25,000 genes.

The researchers also said the new knowledge of the genome sequence will be crucial for breeding and biotechnology advances to increase rice yield, noting that by one estimate the world's rice production must increase by 30 percent over the next 20 years to keep up with demand.

Besides Japan and the United States, participating scientists came from Brazil, China, France, India, Korea, Taiwan, Thailand, and the United Kingdom.